Coal Tar Pitch Preoxidation-Impregnation Regulates Pore Distribution to Prepare Porous Carbon for Electrochemistry

/g and a specific capacitance of 273 F/g at 0.5 A/g. It also demonstrates excellent cycling stability, retaining 95.69% of its capacitance after 10,000 cycles at 5 A/g. The uniform pore structure achieved through KOH impregnation outperformed the carbon material prepared by Yang et al., which showed 93.3% retention under similar cycling conditions. Furthermore, when assembled into a coin cell, the device delivered an energy density of 32.95 Wh/kg at a current density of 1 A/g, surpassing most carbon-based materials reported in the literature. The air preoxidation combined with KOH impregnation produced a porous carbon material with not only a high specific surface area but also a dominant microporous structure, providing abundant sites for efficient charge storage. As a result, OPC-600 exhibits outstanding electrochemical performance. This study provides a novel and efficient strategy for the utilization of coal tar pitch and offers new insights into the design of advanced carbon-based supercapacitors.